Shinsuke Yamanaka and Toshiyuki Ishigara went through very different means to defend their respective championships in the first title fights to hit Sendai, Japan in nearly 30 years.

Yamanaka was explosive in his 7th round knockout of Mexico's Tomas Rojas in their main event. Igarashi's first defense of the lineal flyweight crown was dangerously close to the end of his reign, taking a majority decision over Nestor Narvaez.

Both bouts aired live on WOWOW in Japan.

Yamanaka was in control of the fight before flattening Rojas early in the seventh. Rojas was left face-first on the canvas as he was counted out at 0:36 of round seven.

The win was Yamanaka's second successful defense of the bantamweight belt he won a year ago, almost to the date, as he improves to 17-0-2 (12KO). His first defense came earlier this year, turning back the challenge of former two-division champ Vic Darchinyan.

Rojas falls to 39-14-1 (26KO). The former super flyweight titlist won three straight - all in Mexico - heading into the bout.

Igarashi was forced to work much harder for his win in fending off a determined Narvaez, who was the younger brother of long-reigning super flyweight titlist Omar Narvaez.

The fight was a vicious bloodbath. Igarashi overcame bleeding from cuts over both eyes as well as a point deduction in the 10th round for headbutting. In the end, he was able to outwork Argentina's Narvaez to barely edge out the fight.

Scores were 113-113 even and 114-112 (twice) for Igarashi, who improves to 17-1-1 (10KO). His successful first defense comes less than four months after winning the title from Sonny Boy Jaro in yet another war.

Narvaez fails in his bid to present boxing's next great brother duo. The loss is his first as he falls to 19-1-2 (9KO).

The pair of title fights marked the first time championship action has made its way to Sendai. The last major title fight came in 1983, when Jiro Watanabe won a 15-round decision over Roberto Ramirez for the fourth defense of a lengthy super flyweight title reign.

Jake Donovan is the Managing Editor of Boxingscene.com. Follow Jake on Twitter:
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